Download PDF
Synfacts 2011(3): 0329-0329  
DOI: 10.1055/s-0030-1259447
Organo- and Biocatalysis
© Georg Thieme Verlag Stuttgart ˙ New York

Asymmetric Cyclopropanation Catalyzed by C 2-Symmetric Ureas

Contributor(s): Benjamin List, Ilija Čorić
Y. Cheng, J. An, L.-Q. Lu, L. Luo, Z.-Y. Wang, J.-R. Chen*, W.-J. Xiao*
Central China Normal University, Wuhan, P. R. of China
Further Information

Publication History

Publication Date:
16 February 2011 (online)

    Permissions and Reprints

Significance

The organocatalytic asymmetric cyclopropanation of β,γ-unsaturated α-keto esters 2 with stabilized sulfur ylides 3 using C 2-symmetric bisurea 1 as a hydrogen bond catalyst has been described. The reaction provides access to 1,2,3-trisubstituted cyclopropane derivatives 4 in moderate to good yields with moderate enantio­selectivity (er up to 90:10). Interaction of both substrates and the product with the catalyst through hydrogen bonding has been supported by NMR spectroscopy studies.